So owning a high ranked alt which ranked up long ago, maybe due to airdropped merit, would not count much, except the account has been actively contributing to the forum over the past year.
Also bump score diminishes during a month. A thread bumping service would be difficult to operate, particularly as there's no guarantee that a bump would actually bump a thread.
...and if you post in a thread your "Bump" isn't as effective as if you hadn't posted to begin with. In the ANN thread for bumping IIRC I had to bump about thirty to fifty threads before my bump power was totally exhausted (all the while earning ~40 merits in 120 days - I'm now up to ~100 merits in 120 so if I were to bump the power of said bump would be more effective).